Dear all,
I am doing a project on "Audio Watermarking Using DCT and DWT" using Matlab.I have done the watermarking embedding and decoding but i cant provide the attacks like MP3 compression,cropping,quantization can any one sort out this problem

This site - http://ff123.net/ - has some useful information and links about MP3. I suspect you will need a fairly deep understanding of MP3 encoding and decoding in order to be able to embed information that doesn't get lost.